1. Field of the Invention
The present invention relates to a process of reducing chloronitrobenzenes to the corresponding chloroanilines.
2. Description of the Prior Art
Russian Pat. No. 188,982 and "Catalytic Reduction of Chloronitrobenzenes to Chloroanilines" by N. P. Sokolova et al. N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences of the USSR, pp 1830-1833 (1966) translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp 1891-1895, November 1966, disclose the use of ruthenium supported on barium sulfate as the catalyst for reducing chloronitrobenzene to chloroaniline at pressures of 50 atm. and 100 atm. and temperatures up to 90.degree. C.
Br. 1,064,959 discloses the hydrogenation of halonitrobenzene to haloaniline using a sulfide of platinum, rhodium, ruthenium or palladium as the catalyst. The use of platinum metal catalyst as the control runs is also disclosed.
U.S. Pat. No. 4,164,481 discloses the regeneration of noble metal catalysts which have been used to hydrogenate nitrobenzene to aniline.
U.S. Pat. No. 4,059,627 discloses the hydrogenation of chloronitrobenzene to chloroaniline in the presence of a sulfur compound such as a thioether.
U.S. Pat. No. 4,169,853 discloses the use of solubilized ruthenium-containing complexes in combination with quaternary ammonium hydroxides to effect the reduction of various ortho-substituted nitroaromatics.
Rylander et al., Actes Second. Congr. Interna. Kaltal., Paris (1960), Ed. Technip., Paris (1961), pages 977-985 disclose the reduction of nitrobenzene using ruthenium, platinum, and ruthenium-platinum catalysts.